The present invention relates to lighting and other electrical load technology, and more particularly to a light or other electrical load set circuit, a light strip and a control apparatus for driving the load set circuit. Common light strips typically include an array of light-emitting diodes (LEDs) soldered on wires or conductors of a flexible ribbon board. Such light strips can be inserted into a translucent or transparent tubular member, or directly molded into a device. When the light strip is connected to a power supply, it will emit light, which can look like a light band. It is known that the light color can be changeable and/or dimmable. The light color change can be controlled, with monochrome and RGB effects selected to provide colorful visual effects. Such light strips have been widely used in the decoration and lighting of buildings, bridges, roads, courtyards, furniture, automobiles, signs, etc., for decoration or lighting. The present invention also has application in controlling sets of other electrical loads such as heating elements and motion actuators, for example, motors, solenoids, vibrators, and speakers.
In recent years, light strips are increasingly popular in applications such as wearable devices that are closely related to people's lives, and this role is not limited to decoration or lighting. For example, light strips can be placed on shoes, being activated on or off by closing and opening a switch, LED lights on a light strip can exhibit bright and dark flashing effects, increasing the beauty of the shoes while improving the safety of walking at night. Light strips can also be mounted at the front and/or rear of bicycles. Also, the bright and dark flashing effect acts as warning for improving the safety of night riding. Light strips can also be placed proximate protruding objects for prompting passersby to avoid such dangers.
However, in many applications the number of wires or other conductors and circuitry needed in the prior art for a desired effect becomes prohibitive in that each aspect of control typically requires a separate control line, plus a common (ground) return. For example, in the prior technology, a typical light strip control chip has two, three or four control terminals. Multiple light points are set between these terminals, and each light point includes one or more LED lights, which are turned on or off according to the control level of a corresponding control terminal. When the display of a specific mode is needed, the control signal for a particular aspect needs to be set specially, and LED lights of the light point generally cannot be individually turned on. Alternatively, the control chip can also be provided with enough control terminals so that each control terminal corresponds to one light of each light point. That way the control chip can control the lights of the light points individually, which can provide a greater variety of flashing modes, but the cost is markedly increased for larger numbers of light point lights.
Thus there is a need for an improved circuitry and control apparatus that avoids the need for separate wires for each aspect of a light strip display.